When I tried to get the Promise PDC20276 working in RAID1 mode on my Asus A7V333 running Linux 2.4.19, I encountered a problem due to seemingly confusing docs: According to the instructions on http://people.redhat.com/arjanv/ pdcraid/ataraidhowto.html, and on "Promise Fasttrack RAID Howto" (http://www.magic-lamp.org/howto/pdc20265-mandrake8.2.phtml), I set the kernel option CONFIG_PDC202XX_FORCE (aka "Special FastTrak Feature"). The kernel wouldn't detect the disks on the RAID controller. When I disabled that option (no other changes at all), it worked. What happened in the first case was that the (normal) IDE driver detected my PDC20276 but didn't initialize it, saying "ide: Skipping Promise RAID controller". When the pdcraid driver later probed for the disks on it, it didn't find any (I traced it down to the call to get_info_ptr in calc_pdcblock_offset, which returned NULL for the devices where the disks should appear). When I disabled the offending option, the pdc202xx driver first found the disks and assigned them to /dev/hde and /dev/hdg, and then pdcraid found them too and set up /dev/ataraid/d0 correctly. This is how I run it now, being careful not to touch the /dev/hde and /dev/hdg devices directly. I gather that pdcraid uses pdc202xx for the low level stuff, but the CONFIG_PDC202XX_FORCE option apparently disables that driver. Yet the docs very clearly states that that option should be used. Why? How is it intended to work? Anyway, it's probably a good idea to amend the mentioned instructions to point out that it might be worth trying without "Special FastTrak Feature". Some other info on my setup that might be related: The A7V333 motherboard has another IDE controller, VIA VT8233A, which works as the primary IDE interface. I have another disk and a CD-ROM unit on that one. If you'd like more info, please let me know. NB: I haven't read the ataraid-list archives thoroughly. My apologies if this is an old issue.
